Download the le tute1.csv from the book website, open it in Excel (or some other spreadsheet application), and review its contents. You should nd four columns of information. Columns B through D each...

Download the le tute1.csv from the book website, open it in Excel (or some other spreadsheet application), and review its contents. You should nd four columns of information. Columns B through D each contain a quarterly series, labelled Sales, AdBudget and GDP. Sales contains the quarterly sales for a small company over the period 1981-2005. AdBudget is the advertising budget and GDP is the gross domestic product. All series have been adjusted for ination.

a. You can read the data into R with the following script:

b. Convert the data to time series

(The [,-1] removes the rst column which contains the quarters as we don’t need them now.)

c. Construct time series plots of each of the three series Check what happens when you don’t include facets=TRUE .